Toroid winding machine



Jan. 12, 1965 Filed Juhe so, 1961 M. W. TANNY TOROID WINDING MACHINE 2Sheets-Sheet 1 FIG.I

/4 I I WI! 78 F I G. 2

INVENTOR. MICHAEL W. TANNY BY H/S ATTORNEY 1965 M. w. TANNY 3,165,272

TOROID WINDING MACHINE Filed June so. 1961 2 Sheets-Sheet 2 FIG 6 64 6466\ I I /60- I //I2 n 66 \N a 6% t\\\\ i //7 IO 1 I9 INVENTOR. MICHAELW. TANNY BY H/S ATTORNEY United States Patent 3,165,272 TORGID WINDINGMACHINE Michael W. Tanny, 501 .lefierson SE, Albuquerque, N. Mex. FiledJune 30, 1961, Ser. No. 179,505 9 Claims. ((Il. 2424) (Filed under Rule47(3)) and 35 U.S.C. 118) This invention relates to Winding machines andmore particularly to a toroid winding machine that is especially usefulfor winding magnet wire onto very small toroidal cores.

Until recent years almost all existing toroid winding machines utilizeda separable bobbin that could be linked with the toroid core. Thisbobbin carries the magnet wire which is to be wound upon the core.

This type of toroid winding machine has several inherent distadvantages.One of the greatest disadvantages is that the magnet wire must be woundon the bobbin after the bobbin is linked with the core, thus increasingproduction time and restricting the minimum cross-sectional area of thebobbin. As the bobbin must pass through the toroid core during thewinding operation, bobbin-type machines are restricted to use in windingtoroidal cores having an inside diameter at least twice the diameter ofthe bobbin.

Another important disadvantage of the bobbin-type machine is that theyusually require a shuttle to feed the magnet wire from the bobbin to thecore. As this shuttle or slider must be accelerated by the magnet wirewith each revolution of the bobbin, breakage of the magnet wire is agreat problem when the magnet Wire is of a very small diameter.

Still a third important disadvantage of the bobbin-type winding machineis that all parts must be manufactured to very close specifications,thus increasing the cost of manufacturing the machines.

The present trend toward miniaturization of electronic equipment hascreated a great interest in miniature magnetic cores. Needless to say,it is completely impractical to consider winding these very small coresusing a bobbintype toroid winder. Windings are usually placed on thesevery small cores using hand winding procedures, usually involving theuse of a needle the same as or similar to the hand needles used in thetextile industry.

In an effort to reduce the very expensive and time consuming handoperations, several toroid winding machines have been devised that donot utilize a bobbin as such. Thus, for example, machines have beendevised in which a needle pulling the magnet wire is controlled by oneor more moveable magnets. Although this type of machine constitutes atrue advance in the art in that they have made it possible to wind thevery small miniature cores without resorting to an extremely laboriousmanual operation, difliculties have arisen in accurately controlling thepath of the needle.

The present invention provides a toroid winding machine that is lesscomplex than the prior art machines and therefore more economical toproduce. It is extremely simple to operate yet capable of mechanicallyapplyng windings to smaller toroid cores than was heretofore possible.Using the toroid winding machine of the present invention, cores havingan inside diameter as small as 0.015 inch have been wound with number 50A.W.G. magnet wire.

According to the present invention, a separable leader is passed throughthe toroidal core and one end of the magnet wire is attached to theleader. The leader is held lightly to a rotating disk that supports anddrives the lead er. Due to the unique manner in which the disk supportsand drives the leader, it is practical to use a leader having a diameter0.002 inch or less for winding very small Wire.

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Means are provided to control the loop formed as the wire is wound ontothe toroidal core and to tighten the winding formed on the toroidalcore.

It is therefore, one object of this invention to provide a toroidWinding machine capable of placing windings on toroidal cores of asmaller inside diameter than was heretofore possible.

Another object of this invention is to provide a toroid winding machinethat operates Without a shuttle or bobbin.

Still another object of this invention is to provide a toroid windingmachine that controls the tension of the magnet wire without danger ofbreaking even small diamv eter wire.

Still another object of this invention is to provide a toroid windingmachine that is of a simpler construction and easier to operate thanprevious machines.

These and many other objects and advantages of the present inventionwill be apparent as the following description of the invention unfoldswhen taken in conjunction with the appended drawings wherein likereference numerals denote like parts and in which:

FIGURE 1 is a plan view of a toroid winding machine according to thepreferred embodiment of the present invention;

FIGURE 2 is a view in cross-section illustrating a second embodiment ofthe invention;

FIGURE 3 is a view, partially in cross-section, taken along line 3-3 ofFIGURE 1 that illustrates a tensioning device useful in practicing thepresent invention;

FIGURE 4 is a view, partially in cross-section, illustrating the mannerin which the wire leader may be made separable;

FIGURE 5 is a plan similar to FIGURE 1, but which illustrates a wirecontrol device; and

FIGURE 6 is a view, partially in cross-section, taken along line 66 ofFIGURE 5.

Turning now to the detailed description of the invention and moreparticularly to FIGURE 1 of the drawings, a relatively large disk 10 isshown. A groove 12 is formed in the upper surface of the disk 10 that isconcentric with and slightly removed from the edge of the disk 10. Thepreferred configuration of the groove 12 is best illustrated in FIGURE3. A series of axially spaced holes 14 that contain permanent magnets 16are formed in the base of the groove 12.

As best seen in FIGURE 2, the disk 10 is positioned within a hole formedin a mounting plate 17 on a bearing 19 and driven by suitable means suchas an electric motor 18 and pulley arrangement 21. The motor 18 shouldbe of the variable speed type. The core 20, upon which the winding is tobe wound, is held by a core holding fixture 22, above the groove 12, ata height slightly above the upper surface of the disk 10 with its axisperpendicular to the radius of the disk 10 at that point.

The core holding fixture 22 may be either a very simple vice-typeattachment or a more complex fixture capable of rotating the core as thewinding is applied, depending upon the type of winding required.

A tensioning device designated generally by the reference numeral 26 islocated adjacent the rim of the disk 10. Referring to FIGURE 3 of thedrawings, the tensioning device 26 comprises a pair of spring members 28and 30 mounted on a post 32. The lower spring member 28 is shaped todefine a notch that extends down into the groove 12 and then up abovethe surface of the disk 10. The upper spring member 30 extends acrossthe groove 12 and contacts the lower spring member 28 at region 34.Screw 38 controls the pressure with which spring member 30 bears againstspring member 28, thereby controlling the tension on the magnet wirethat is necessary to cause the wire to slide between the spring members28 and 30.

The inwardly projecting portion 5t) of the groove wall is desirable tocontrol the magnet wire 48.

The leader 40 used in practicing the invention is preferably of a verystifi material of high permeability, such as spring steel wire. FIGURE 4shows one manner in which the leader 40 may be assembled to form aseparable loop. As illustrated, one end 42 of the leader 4% is connectedto a thin bushing 44 by soldering or other means. The joint between thebushing 44 and the leader 44 should be tapered and smoothed to preventdamage to the insulation on the magnet wire 48 that is Wound on thetoroidal core. leader 40, the other end 46 of the leader 49 is insertedin the open end of the bushing 44. The resiliency of the leader 4t} willcause the separable loop to be maintained.

The magnet wire 48 that is to be wound on the core may be attached tothe leader 4th by either knotting the Wire aroundthe end 42 of theleader 4t) adjacent the To assemble the separable loop formed by thebushing 44 or a hole 45 can be provided in the bushing 44 in which themagnet wire 48 is inserted as shown in FIGURE 4.

To operate the machine, a toroidal core having the desired size andmagnetic characteristics is inserted in the core holding device 22. Aleader having a length slightly longer than the circumference of thegroove 12 is threaded through the tensioning device 26 as shown inFIGURE 3 and through the core 29. The leader 4th is then assembled asshown in FIGURE 4 to form a separable loop and the magnet wire 48 thatis to be wound onto the core 20 may then be attached to the leader 40 asshown in FIGURE 4 or by the simple expedient of tying themagnet wire 48to the leader 40. The motor 18 is then operated causing the disk it torotate until a length of magnet wire 43 approximately equal to thecircumference of the disk 10 has passed through the core 20. At thistime the motor 18 is stopped and the loose I end of the magnet wire 48is either held by the operator or tied to the core-holding fixture 22.

The magnets 16 placed in the small holes 14 hold the leader 4t lightlyagainst the bottom of the groove 12, thereby maintaining the position ofthe leader 4% relative to the disk 10. However, the force of attractionbetween the leader 40 and the magnets in is small enough that the coreand tensioning device can easily hold the leader away from the bottom ofthe groove 12 as'necessary. Except for the portion of the leader 4% thatis raised up by the core-holding device and the tensioning device, the

magnets will maintain the wire lightly held against the rotating plate.

After the loose end of the magnet wire 48 has been secured, the motor 18is again turned on causing the disk 10 to rotate. As the disk 10 rotatescarrying the end of the magnet wire 48 connected to the leader 4d in acircular path, the magnetic wire 43 tends to slide across the top of thedisk 10 due to the placement of the core 29 slightly above the uppersurface of the disk 10. However, before the magnet wire 48 can slideacross the top of the disk '10, it must pass through the tensioningdevice 26 thereby removing any slack that may be in the magnet Wire 43at this point.

As the leader 40 moves in a circular path due to the rotation of thedisk It the magnet wire 48 moves across the surface of the disk 10forming a loop as shown in FIGURE. 1. That portion of magnet wire 48 notsliding across the upper surface of the disk it is maintained in groove12 by the inwardly projecting portion 59. When that point of the leader4d to which the magnet wire 48 is attached again passes through themagnetic core 20, the

loop is completed but is wound ontothe core 29 in a very loose manner.The leader 40 again carries the magnetic Wire 43 through the tensioningdevice 26 causing the newly formed loop to be tightened before themagnet wire 48 can again begin to slide across the upper surface of thedisk 10.

This cycle is repeated until the desired number of turns have beenplaced on the magnetic core 20. It is practical to place an electroniccounter 49 that is actuated by a cam operated micro-switch on themachine to record and count the number of turns of magnet wire 48 thathave been placed on the magnetic core 2%.

in operating the machine, it has been found desirable to provide a meansfor controlling the magnet Wlf6 4s as it slides across the surface ofthe disk It) to insure that the magnet wire 48 does not become tangledor knotted. FIGURES 5 and 6 illustrate a means for controlling themagnet wire 48 whereby a stationary plate 60, provided with a band 62 offelt on its bottom surface, is positioned above the top surfaceof therotating disk 10. The band 62. of felt tends to hold the magnet wire 48such that a definite tension is required to cause it to move across theface of the rotating disk 10, thereby effectively controlling themovement of the magnet wire 48. The plate as may be supported by straps64, attached to the plate 69 and blocks 66 mounted on the mounting plate17. The spring members 28 and 36B of tensioning device 26 extend overthe surface of the rotating disk it a short distance to insure that themagnet Wire 48 will feed between the felt 62 and disk 30.

Instead of magnets, a vacuum system can be utilized to hold the leader4% lightly against the disk it). According to this embodiment of theinvention, the holes 14 are open and extend into the chamber formed bythe disk 10 and case '72. Gasket means are provided between the disk 10and'the mounting plate 17 to restrict the flow of air. A suitableopening '76 is formed in one part of the mounting case '72 and a vacuumpump 78 is connected to the opening 76 through tubing 80. When thevacuum pump 78 is operated, the flow of air down through the holes 14 issufficient to hold the leader 4% lightly against the base of the groove12 in the disk iii much in the manner of the magnets 16. The vacuumsystem has one advantage in that it assists in controlling the magnetWire 48. However, this mcthod is not as satisfactory as the one utilizedin the magnets in that the construction utilized in the magnets issomewhat simpler and less expensive to manufacture and maintain.

From the above description is it evident that 'a toroid winding machinecapable of Winding almost any size magnet wire upon any size toroidalcore has been provided The machine is exceedingly simple to manufactureand operate, yet very reliable in its operation. Although the inventionhas been described with regard to only two preferred embodiments, manychanges and modifications would be obvious to those skilled in the art.The invention, therefore, is not tobe limited to what is shown ordescribed herein, but only as necessi tated by the scope of the appendedclaims.

What I claim is:

p l. A toroid winding machine comprising a rotatable member having anupper surface, means for rotating said member, means for supporting atoroidal core at a point adjacent to but spaced apart from saidrotatable member, a leader for pulling a strand of wire through saidcore to form a loop, said strand of wire passing over, said uppersurface as said loop is formed, and means-for holding said leaderlightly against said rotatable member to produce rotation of said leaderresponsive to rotation of said member.

2. A toroid winding machine as defined in; claim 1 wherein said memberdefines a disk.

3. A toroid winding machine as defined in claim 2 wherein said leaderdefines a separable ring.

4. A toroid winding machine as'defined in claim 3 including additionalmeans to tension said strand of Wire and tighten said loop about saidcore.

5. A toroid winding machine as. defined in claim 4 including controlmeans for controlling the movement of saidwire across said upper surfaceas it forms a loop.

6. A toroid winding machine as defined in claim 4 wherein said leader isof a magnetically permeable material and said means for holding saidleader lightly against said disk comprises a plurality of magnets.

7. A toroid winding machine as defined in claim 4 wherein said means forholding said leader lightly against said disk comprises a vacuum system.

8. A toroid Winding machine comprising a rotatable disk having an uppersurface, means for rotating said disk, means for supporting a toroidalcore at a point adjacent to but spaced apart from said rotatable disk, aseparable leader for pulling a strand of wire through said core to forma loop, said strand of wire passing across said upper surface as saidloop is formed, tensioning means for tightening said loop about saidcore, means for controlling the movement of said wire across said uppersurface as said loop is formedand tightened, and magnetic means 152,963,777

References Cited in the file of this patent UNITED STATES PATENTS2,812,143 Goodykoontz Nov. 5, 1957 2,865,086 Whipple Dec. 23, 19582,865,573 Tarara et a1. Dec. 23, 1958 2,894,699 Onisko July 14, 1959Starr Dec. 13, 1960

1. A TOROID WINDING MACHINE COMPRISING A ROTATABLE MEMBER HAVING ANUPPER SURFACE, MEANS FOR ROTATING SAID MEMBER, MEANS FOR SUPPORTING ATOROIDAL CORE AT A POINT ADJACENT TO BUT SPACED APART FROM SAIDROTATABLE MEMBER, A LEADER FOR PULLING A STRAND OF WIRE THROUGH SAIDCORE TO FORM A LOOP, SAID STRAND OF WIRE PASSING OVER SAID UPPER SURFACEAS SAID LOOP IS FORMED, AND MEANS FOR HOLDING SAID LEADER LIGHTLYAGAINST SAID ROTATABLE MEMBER TO PRODUCE ROTATION OF SAID LEADERRESPONSIE TO ROTATION OF SAID MEMBER.